Hi Discord Team and dear reader!
This would be a feature request for Message Threads, like we can see on Slack.
As a matter of fact, when sending messages in a crowded channel (+15ppl) conversations can easily get lost in the mix. Message threads solve this issue by creating a "sub-channel" on the message that initiated the thread, allowing participants to continue their conversation without spamming the main channel and allowing other users to do the same.
Thanks a lot,